Normally I wouldn't attempt to address an issue in this manner, but since it is getting a bit out of hand, and usually on boards I'm not participating in (or have little desire to participate in), I'll try and address it officially, once, in the place where it should be the most relevant.

The matter I'm discussing is related to the --alt-presets and their handling of the "stereo image".

There have been some completely unsubstantiated reports and rampant speculation going on in a few threads which I will list below:

2. All of the vbr presets provide better sound quality via joint stereo than LAME on it's own with joint stereo, and in some cases should even sound better than with --nssafejoint, while at the same time providing a lower bitrate.

3. The --alt-presets do not, by design, make any sacrifice in regards to stereo image to keep bitrate down. Anyone who tells you this has no idea what they are talking about. I should know since I actually wrote the code and designed the presets.

4. An extremely high degree of stereo frames is not always needed to achieve good sound quality. I challenge anyone who believes that --alt-preset standard has poor stereo seperation, on a common basis (as a few unsubstantiated claims imply), to provide me with direct evidence of this.

5. Joint stereo is needed even at bitrates of 320kbps to achieve the best sound quality in some critical cases. Forcing stereo on everything up to 320kbps and then forcing joint stereo does not fix the problem (as user implies in one of those threads). I've tried this before.

6. There seems to be a misconception that all that the --alt-presets improve on are pre-echo. This is sorely mistaken. Indeed they do improve on pre-echo and impulse handling to a fairly large degree, but they also improve upon:

- joint stereo handling (serioustrouble is a prime example)
- dropout prevention (2nd_vent_clip is a prime example)
- fluttering (gekkou is a prime example)
- knocking (velvet is a prime example)
- ringing (bloodline is a prime example)
- noise pumping (piano, rach_original, etc, are examples)
- rasping (present with noise shaping 2 on some clips like fatboy, or on clean vocals sometimes. Mostly eliminated, even on the most critical samples, with --alt-presets)

And that's just the stuff I can think of off the top of my head.

Now, that's not to say the --alt-presets are perfect. I certainly know they aren't. But they also don't have some massive flaw in regards to stereo image which is present to the degree some people imply. In fact, the only case I've seen which I put any credence in is the few isolated cases which Wombat has found (and provided samples for I might add). I will eventually attempt to address these few samples, but note that these are exceptional cases, not common cases, and as far as I can tell, they are completely unrelated to the other complaints being made. This is especially so since Wombat doesn't describe the artifact as being a collapse of the stereo field (which isn't your typical joint stereo artifact in LAME anyway...).

At any rate, I'm always looking to improve things if I can, but claims must be substantiated which includes providing abx results (which are then verified by other parties) and providing test samples, preferrably multiple ones if you are implying a problem with general behavior.

Not to come across arrogant, but for the most part, I'm the only one who truly understands the workings behind the --alt-preset specific tunings. Not even the other developers have followed my work (though that's by their choice, not mine). The code is available for all to see, but so far I have not seen anyone attempt to reimplement my modifications or to discuss them with me on a technical level. So unless you see someone who is closely related to the work I've done (ie, they have participated in testing, JohnV for example) stating something, or you see me stating something directly about the presets, then chances are whoever is discussing the presets doesn't have the full picture. This is especially true when people begin discussing how the --alt-presets work internally or technically, and especially in relation to joint stereo.

If you see a discussion on another board about these issues, please point people to this thread. If you have a question, please ask me here, you'll likely get a much more correct answer in addition to helping to keep questions about this issue centralized and concise (which will help when the FAQs are created). Speculation is not only wasteful, but it also helps to propogate misinformation such as the old "joint stereo is bad" line of thinking.

Originally posted by rc55 I'd say it'd be a good idea to keep this topic either sticky and/or locked.... Unless Beatles has anything to say!!!

Perhaps I'll make it sticky.. we'll see.

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Also... perhaps you could make a facility for submitting difficult samples with ABX data or whatever.

Probably a good idea. Unfortunately, I've been so busy lately that I haven't really been able to move the site in the direction I've been hoping for. I've been working on a remedy for that though, but it might still be a ways off. I'd really like to make this site more functional and user friendly though so stuff like what you suggested is certainly in mind

It's a many-headed hydra. Just as soon as one can show that a particular individual setting is inferior to --alt-preset standard (such as -q0 -V0 -b160 --athlower 1 lowpass 20.5), another one pops up with an additional tweak ("This one gets close to or is as good as aps, which sounds 'brash' to me, maybe even better because aps uses joint-stereo, which must logically degrade the stereo image; and what's more, I didn't even try hard, just used the default settings with a couple of tweaks -- aps must be in need of improvement!").

In one thread, I took two easy-to-hear samples, showing just two different types of artifacts on which --alt-preset standard is superior to the command line in question. But rumors die hard -- since I didn't listen to samples which might possibly have stereo separation problems (although I am willing to upload reasonably short samples to my page -- no multi-hundred megabyte files, please), the argument goes, aps may be inferior in that regard.

I think the best way to kill off inferior command lines is to test them one by one. But perhaps there should be some record which documents each death. And for those that refuse to die, just keep adding samples

Originally posted by ff123 It's a many-headed hydra. Just as soon as one can show that a particular individual setting is inferior to --alt-preset standard (such as -q0 -V0 -b160 --athlower 1 lowpass 20.5), another one pops up with an additional tweak ("This one gets close to or is as good as aps, which sounds 'brash' to me, maybe even better because aps uses joint-stereo, which must logically degrade the stereo image; and what's more, I didn't even try hard, just used the default settings with a couple of tweaks -- aps must be in need of improvement!").

Indeed. One of the biggest problems also is that there are no real controls in the comparisons that other people are making. For example, they are testing largely on non-critical samples (being defined as those which L.A.M.E. and other mp3 encoders are known to have problems on), not enough of these samples, not enough people are verifying their results, and I'd dare say that often there are not enough "sensitive" listeners participating. Really, all of that is pretty much an understatement..

QUOTE

[b]In one thread, I took two easy-to-hear samples, showing just two different types of artifacts on which --alt-preset standard is superior to the command line in question. But rumors die hard -- since I didn't listen to samples which might possibly have stereo separation problems (although I am willing to upload reasonably short samples to my page -- no multi-hundred megabyte files, please), the argument goes, aps may be inferior in that regard.

Perhaps another problem is that people give to much credit to unsubstantiated claims. I'm very skeptical myself, as are some other people on this board, mainly because there have just been so many cases where the problem turned out to be non-existant, or when verification was called for, the person just disappeared. I guess I just prefer to take a "guilty till proven innocent approach" (where "guilty" is a non-existant problem), and so I naturally require proof of claims. A lot of people don't seem to take this approach though.

The bottom line that people need to realize is that there can be no fixing of a problem if it cannot be substantiated. You can't improve upon something if you don't see it's flaws. This means that if someone is complaining about something, they [b]must provide evidence of what they are describing or it's basically useless to everyone interested in real progress.

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[b]I think the best way to kill off inferior command lines is to test them one by one. But perhaps there should be some record which documents each death. And for those that refuse to die, just keep adding samples

This actually sounds like a good idea. To go further, I've thought about compiling a package of test samples where L.A.M.E. and other MP3 encoders have trouble with, but where --alt-preset standard does very well. For each new command line someone thinks they can come up with that is superior (which really isn't possible without code modifications... but oh well), they can test against these samples. If there is a significant enough score in favor of their line (somehow taking into account quality, size, and the quality/size ratio or "efficiency") vs --alt-preset standard, then perhaps there is some merit to the other line and it warrants further investigation. This would really provide an easier way to verify the results quickly and efficiently. The list of which lines were inferior (along with release date) could then go in a FAQ of sorts.

Well, sincerly i can't understand why LAME have so mutch parameters. I think it could move to an "OGGDrop-like" interface: just set the bitrate (or the quality) and the application automatically choose the best settings.
Keep things simply... and leave many options you like for developers !

As a Psychologist (forgive me ahead of time); I see this kind of thing all the time- someone puts X number of hours into something and almost immediately people start looking for flaws- real or not. They feel they must devalue someone elses work to validate themselves. Dibrom says he makes no claim his work is perfect- he never did- but it sure sounds good to these old ears when I use it and listen to the results.
I can't write code- I wish- and just try to soak in as much knowledge as I can from this site- but thanks to everyone who contributes (especially Dibrom, of course). Dibrom, joke 'em if they can't take a f--k!! To the critics- Jealousy and envy are wasted energy- if you find a problem- document it and post it. Sorry to ramble- just tired of seeing people who work so hard at something so creative get criticized for going 'outside' the circle and working on their own and getting ripped for it.

Originally posted by cadabra3 As a Psychologist (forgive me ahead of time); I see this kind of thing all the time- someone puts X number of hours into something and almost immediately people start looking for flaws- real or not. They feel they must devalue someone elses work to validate themselves.

There's nothing wrong if people look for real flaws from settings like alt-presets or different codecs - that's the way things are developing, so it's only a good thing. All devs here agree that their work must be tested and challenged, so that best possible results can be achieved.

The problem is unproven claims and rumors and lack of knowledge.
And sometimes people just want to use something they "discovered" themselves and think it's good enough for them. That's fine as long as there aren't any unproven claims made publically...

I think the best way to kill off inferior command lines is to test them one by one.

ff123

You know, I actually had to prove this to myself. To make a long story short, I bought a new DVD player that has MP3 support. I popped in one of my APS cd's to see how it sounded. It sounded horrible. I already knew the APS sounded good on my JVC car mp3 player.

Hmmmmmm.....

So, after tyring a few things (CBR/VBR), I decided to try a different encoder (some fhg variant). Anyway, it sounded bad too. The problem is defintely the hardware decoder on the DVD player.

In the process of doing this, I thought I would test this other encoder by downloading one of the test clips that everybody talks about. I chose "fatboy".

Well, with my Sony V6 headphones, I could EASILY hear how badly this other encoder mangled the soundclip. In addition, I tried a boatload of different command lines with LAME (including r3mix). Nothing, and I mean nothing, even remotely came close on this clip except APS. I didn't need to bother with APX.

Granted, this is an extreme soundclip, but it is a valid piece of music. The ablity to accurately reproduce it should be a requirement for any encoder. Ogg at medium quality did pretty well by the way.

This test proved to me that there was no combination of LAME command line switches that would accurately reproduce this soundclip, save for APS.

To sum it up: what is an improvement to one person, might be a quality lowering for another.

like: I'd never use the normal "--alt-preset standard" because that 18.6-19.2 kHz lowpass is too low for my taste, but for someone that hears like up to 17kHz this wouldn't be an issue while some echo problems I don't hear in --r3mix might be for them.

So, Roel seems to say that he can hear a difference because of lower lowpass than --r3mix, because he would never use --alt preset standard because its lowpass is lower. Also Roel seems to have the wrong impression that --aps is just a pre-echo fix... oh well..

no-one hears the difference between a 19.5kHz lowpassed signal and the same full-range clip in a double-blind test. It's been proven by science many times before (even with 18.5khz on a very significant number of youngsters) and I did the test myself on my site&forum. In a poll only two people claimed they heard a difference between a 18.5khz and a full range one and the difference was gone at 19kHz. The 19.5 is an extra safety margin.

[b]To sum it up: what is an improvement to one person, might be a quality lowering for another.

I don't buy that at all. I've seen this argument before, and it's always from someone who doesn't want to accept something which has been proven to be superior (ie, people who make up their command lines in disregard to evidence continually backed up and verified by the community -- what this very thread is about).

I've never really seen this verified, that being an improvement to one person being a degredation to another with almost all other things being equal.. and 19khz vs 19.5khz is not significant especially when one consider the logarithmic nature of hearing and the fact that most people probably can't hear beyond 18 or 18.5khz in real music. But then, when you consider the source, someone who is willing to use frequency analysis to judge quality, perhaps that is to be expected.

It doesn't really seem to hold water anyway when compared against community data. Not only has Roel's own AQ test implied (if not directly showed) that the old dm-preset standard was better than --r3mix, I don't believe I've seen a claim since the last few revisions of --alt-preset standard to where someone found --r3mix better. Even if I've missed one or two, the ratio of samples where --r3mix fails badly vs where --aps sounds fine is very high.

At this point, to ignore all of the improvements that have been made (which many people can hear, just look through the revX threads), it'd have to simply be denial I think. Continuing to state, given that evidence, that --r3mix is CD Quality still, supports that as well.

QUOTE

[b]So, Roel seems to say that he can hear a difference because of lower lowpass than --r3mix, because he would [b]never use --alt preset standard because its lowpass is lower.

And of course, we probably won't see any evidence to back up the claims that he can hear the difference between 19khz and 19.5khz. What's worse, he doesn't believe in ABX.. so good luck with that

QUOTE

[b]Also Roel seems to have the wrong impression that --aps is just a pre-echo fix... oh well..

Perhaps this isn't particularly surprising given the history of reaction towards the dm-presets on his board. If one didn't consider those developments significant then, it probably wouldn't be a stretch for them to think the same now.

At any rate, it would be interesting to see --r3mix develop further (though I feel that "third party presets" with someone's name on them are counter productive towards to goal of simplication and user friendliness at this point; LAME needs consolidation, not further fragmentation), but I can almost guarentee that quality improvements cannot be had without increasing size at all, as Roel seems to think is possible. I've worked on this issue very significantly, and it just isn't going to happen. The only way it could be possible is if there were some pretty major changes to the psymodel, and I don't see that happening anytime soon. Furthermore, I feel that LAME is as far as it can be taken just by combining different combinations of command lines. That's why months ago I decided to delve into the code instead...

We'll wait and see what happens, but it seems like someone is expecting a miracle, and it just ain't there What's more, in the past Roel has not shown concern for fixing the many samples which have caused problems in the past and has played down the matter, saying that the person must be abnormal and perhaps should not use MP3 or should normalize their file first or something else. I'd be simply astonished to see the approach to this change now. When you have one person who is apparently unable to hear faults, does not seem to show interest in scientific methodology (abx), is willing to rely on flawed techniques for comparison (freq analysis), and seperates himself from people with sensitive hearing who could help improve things, how can you possibly expect much progress? Take MPC, PsyTEL, or Vorbis for example... if this was the approach used there, they wouldn't be anywhere near the level of quality they are currently at.

And personally I still don't see how 192kbps average is "too high" of a bitrate, especially since the mp3 groups have been trading in this format for years.... I think most users feel this way these days also considering the explosive growth of the use of the --alt-presets.

So at the end of the day, using the bitrate excuse and the .5khz difference in lowpass as reasons for ignoring --aps, just seems like a last stand... an unwillingness to embrace improvements simply for the sake of pride and being stubborn.

[b]I've never really seen this verified, that being an improvement to one person being a degredation to another with almost all other things being equal..

Well, the concept doesn't seem flawed to me - lowering the lowpass frees up extra bits for lower frequencies with a trade-off of throwing away high-frequency data. If you were to lower the lowpass further, to say 16 kHz, you might well increase quality for people whose hearing is not sensitive to frequencies above 16 kHz, since you'd free up more bits for the <16kHz frequencies. But you'd have a trade-off of decreased quality for people who could hear the now-missing high frequencies.

In this particular example I agree that the 19 kHz to 19.5 kHz difference is almost certainly too small and still at too high of a frequency to make an audible difference, but I don't think that shows that the concept of lowering a lowpass being a tradeoff is wrong - it just shows that in this case the tradeoff is a very good one, as the reduction in frequency is either completely inaudible or inaudible only in extreme cases (but it it is still theoretically there - if someone were to encode a 19.25 kHz sine wave, there are people who would be able to hear it, while -aps would chop it off).

In any case I suppose that's a nitpick, I still agree with your entire analysis about Roel's claims being wrong. Especially giving the lack of any evidence, I'm not inclined to believe that raising the lowpass back up to 19.5 kHz would improve music quality for any listeners.

Yes, nitpicking aside... it perhaps is possible (anything's possible, right? ), but being aware of the context it is being discussed in and the context the original statement was made in, it's almost certainly not the case. Even then, as already stated, it's unlikely to be the case in the vast majority of situations, and even more so since I said specifically "with almost all other things being equal", which implies a lack of another area where quality would have been compromised in the particular situation.

JohnV- no disrespect intended- if you read a little further down, I just said, that if you think you find a flaw or problem- document it before announcing it to the world. Of course we would get nowhere if we didn't question things; I believe you're old enough (as I am) to remember the phrase 'question authority'. The one I try to forget is ' don't trust anyone over 30' !! Anyway, I was just trying to say I appreciate the work (and help) on this site and blind criticism with no data to test is useless. Sorry if I offended anyone. -a survivor of the 60's- cadabra3

Originally posted by Pio2001 Roel didn't say he would never use APS, he was just giving an example of what someone not willing to use it could say.

Really? Most of the time what they say is "My setting is better! Use '-v0 -q0 -ms -k --lowpass 22.05'. With this setting the sound is no longer muffled, stereo image is conserved, and it doesn't sound so bad with those artificial sine sweeps I create using CoolEdit/SoundForge"

Also one thing to consider when comparing this small lowpass difference and saying --aps might sound muffled to very young people when compared to --r3mix, is of course ringing and high freq accuracy in general.

If a very young person might be able to hear a difference here (very unlikely but I won't say impossible), it's even more likely one will also hear the increased high frequency ringing of --r3mix.
But of course Roel didn't consider this aspect.. only what it looks like "on a paper"..So, Roel's attempt to downplay --aps with lowpass issue is pretty ridiculous considering that.

Originally posted by JohnV Also one thing to consider when comparing this small lowpass difference and saying --aps might sound muffled to very young people when compared to --r3mix, is of course ringing and high freq accuracy in general.

If a very young person might be able to hear a difference here (very unlikely but I won't say impossible), it's even more likely one will also hear the increased high frequency ringing of --r3mix. But of course Roel didn't consider this aspect.. only what it looks like "on a paper"..So, Roel's attempt to downplay --aps with lowpass issue is pretty ridiculous considering that.

Indeed. Not only is the insinuation that --alt-preset standard will encode less hf because of the slightly lower lowpass extremely misleading, it is also flat out incorrect, as I illustrate with these graphs below:

In this sample you can see --alt-preset standard encoding up to the same level as --r3mix, except if you look closely you notice that --r3mix actually encodes less hf because of the "ringing" artifact! This manifests itself as the short chunks of "missing audio" you see in the --r3mix sample.

This sample flat out shows that --r3mix simply isn't encoding as much high frequency content as --alt-preset standard. The cut for the --r3mix sample is nominally around 13khz in this sample and sometimes even fails to encode beyond 11khz, while in --aps it ranges from 13khz to 16khz, spending more time on the 16khz side. Furthermore, in the --aps sample, there are multiple cases where it actually spikes up to around 18.5khz, where in --r3mix the most you see is 1 time it barely reaches 18khz.

Here is another clear cut case where --r3mix simply fails to encode more high frequency content than --aps despite the fact that --aps has a slightly lower lowpass. What you see here is that --r3mix fails to encode a fairly large portion of the peaks present in the signal. --aps on the other hand, does a much better job, and encodes the impulses nearly completely, all the way to 19khz.

If the examples here don't clearly show the falsity behind the insinuation that --r3mix encodes more hf content (which is what was implied with the fact that Roel pointed out the lower lowpass of --aps as being some sort of fault), then I don't know what does. In many of these cases, --r3mix fails to encode hf content to the degree of --alt-preset standard, and this is far below the 19.5khz area!

This (mis)representation of the facts (in the statement made about the lowpass being too low), though, is what you can expect when you don't pay attention to the (irrelevant?) details

The bottom line is that [b]despite the lower lowpass, --alt-preset standard encodes more high frequency content, with more accuracy, than --r3mix.

Originally posted by JohnV Hey Dib, a bit OT. Could you make those pics a bit smaller size, maybe link for full size pics.
I mean loading of this thread takes some serious time with lower connection speeds atm..

It was a hassle to make the pictures due to my current setup (copy from one pc, load cool edit, snapshot, crop, copy to another pc to burn pictures, copy to another to upload them.. heh), so I'll just change it to links instead of resizing. However, the thread should (and I think it does..) load completely, as far as text, before the pictures pop up so I don't think it should have a detrimental effect.. but oh well

That is some hard evidence, Dibrom! It may not exactly be on topic but I would like to comment on the "youth hears more hf" statement.

Short version: young folk (rough estimate: up to 14 years) do not have trained hearing. Almost anything sounds good to them. They enjoy the music itself and not it's good or bad reproduction. Many young adults kill their ears in discos. Both do not need hf reproduction so discussion focusing on this group of people is irrelevant.

Long version:
The question is, how relevant is hf reproduction for "youngsters"? From personal experience I wish to claim that it is not until a certain age that young people will start to actually listen to music. After taking that step it takes a while for them to develop a feeling for what sounds good or bad. After this it takes yet another while until they start to actually demand quality and understand what this means. Very many (young) people still take 128k fastenc quality as transparent and they experience no gain when going any higher. It takes time to get "educated" in terms of listening.

Probably most are listening on relatively low fidelity equipment ( --> flaws in hf reproduction) especially poor PC speakers when it comes to mp3 (ok, so they burn to CD too and listen through their rel. cheap stereo) and wouldn't be able to make out the difference anyway.

Another point is that a whole bunch (of older teenagers and up) visit discos/clubs almost every weekend where their ears get blasted by very high volumes on setups that are tuned by people who themselves have ruined their hearing and compensate for their hf hearing loss by boosting the treble way too much, thus resulting in even faster loss of the hf hearing of the visitors. In 10-20 years we will be facing a large mass of people with damaged hearing. I cringe whenever I enter such a freakin' loud place. (On a side note: more and more people start to wear ear plugs when they go to discos or concerts. How about turning down the volume?)

A small anecdote: on a trance music related forum some DJ said that after spinning for a while he could no longer hear the bass drum in his headphones. It turned out he had the main speakers directly behind him hammering in on his ears at close range. After some discussion about hearing loss and some "Dude! Are you mad?!" and talking about his sucky headphones he decided to go for louder headphones with better bass reproduction... (wonder how he kept the needle from skipping; probably added a lot of weight )

Conclusion:
I guess what I'm trying to say (not so sure there myself ) is that this whole discussion about satisfying younger people with hf repro is overhyped. Claiming that a 13 year old will much rather listen to an encode with more high frequencies is simply not true (see long version). Young folk around 20 ruin their ears anyway so they don't care either. You loose more hf hearing capabilty the older you get.

Then there is the group of people who demand high fidelity and have the hearing to enjoy it (not only focused on hf of course). Those are the ones we are trying to please. Not "ignorant" children or half deaf clubbers. Discussion should focus on the needs of people who require high quality! Arguing wether or not a five year old would percieve the hf in some specific encode is just irrelevant.

What I have said is not based on research just on some thinking I've been doing, so please speak up if you know better! (Phew! Longest post I've ever done on this forum )